Recently, a plurality of communication providers provide wireless communication services, such as mobile phone services. The communication providers deploy base station devices in every region in order to establish communication networks that cover communication areas nationwide. Further, each of the communication providers independently deploys each base station device in the same region.
In the communication networks as described above, there is a problem with the continuity of wireless communication services in the event of a major disaster. If a major disaster occurs, base stations and networks deployed in affected areas may be broken, and it may become difficult to continuously provide wireless communication services to users. Communication infrastructures, in particular, mobile communication infrastructures, are lifelines closely connected to normal lives; therefore, the communication providers aim at providing continuous wireless communication services without disconnection even when a disaster or a failure occurs.
For the purpose of providing continuous wireless communication services at the time of a disaster, each of the communication providers independently take countermeasures.
For example, there is a method of deploying a large-zone base station that is not used at normal times but is used at the time of an emergency. The large-zone base station has a greater coverage than an ordinary base station. The large-zone base station does not provide services at normal times, but provides services and ensure the continuity of wireless communication services when an ordinary base station device is unable to provide services due to a disaster or the like.
Further, there is a method of putting a repeater on a balloon after a disaster, floating the repeater at the height of 100 meters, and causing the repeater to relay radio from the ground in order to take over the functions of a broken base station device.
Alternatively, when a base station or a network of a certain communication provider is broken, it may be possible to employ a method of using a system of other communication providers by using roaming in order to continue wireless communication services.
As a technology for wireless communication services, conventional technologies as described below have been proposed. For example, there is a conventional technology for sharing a wireless network with a plurality of communication providers and charging usage fees depending on use. Further, there is a conventional technology for causing a plurality of communication providers to share a wireless unit that communicates with terminals and causing a wireless control unit of each of the communication providers to control the shared wireless unit. Furthermore, there is a conventional technology for complementing deficiencies of functions of a system by borrowing and lending base stations among different communication systems.    Patent Literature 1: International Publication No. 2005/039211    Patent Literature 2: Japanese Laid-open Patent Publication No. 2013-65977    Patent Literature 3: Japanese Laid-open Patent Publication No. 2001-128237    Non Patent Literature 1: NTT DOCOMO, INC., DOCOMO Deploys Two Large-Zone Base Stations in Tokai Region, [online], Sep. 29, 2001, NTT DOCOMO [searched on Apr. 17, 2014], <URL: https://www.nttdocomo.co.jp/info/news_release/2011/09/29_00.html>    Non Patent Literature 2: SoftBank Mobile Corp., Results of demonstration experiment of a balloon moored radio relay system, [online], Mar. 1, 2013, SoftBank Mobile Corp. [searched on Apr. 17, 2014], <URL: http://www.softbank.jp/corp/group/sbm/news/press/2013/20130301_01/>
However, in the method of using a large-zone base station, a large-scale facility is additionally installed, resulting in a large increase in costs. Further, in the method of floating a repeater with a balloon, the repeater and the balloon are delivered to an affected area; however, it may be difficult to promptly deploy the repeater because of degradation of road conditions or the like after a disaster.
Furthermore, in the case of using roaming, it is difficult to reach agreement on roaming among domestic communication providers because of relationships of rights. Therefore, it is difficult for communication systems to interoperate with one another at the time of a disaster under a proper agreement.
Moreover, in the method of sharing a wireless network or a wireless unit with a plurality of communication providers, it is difficult to share the network or the unit among existing communication providers because of the same reason as in the case of roaming; therefore, it is difficult to continuously provide services at the time of a disaster. Furthermore, in the conventional technology for borrowing and lending base stations among communication providers, resources available to the communication providers serving as lenders are reduced, so that wireless communication services may be degraded.